Name change of the invasive fruit fly and update on its pest status in South Africa

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1 Name change of the invasive fruit fly and update on its pest status in South Africa Fruit flies are the bane of many fruit growers existence, but in this case it s better the devil you know, than the one you don t... For some time now the scientific community was worried about an unwelcome foreigner called, B. invadens, but recently scientists agreed that this was in fact B. dorsalis (Oriental fruit fly). Bactrocera invadens was recently synonymised with Bactrocera dorsalis based on evidence of similarities in morphological characters, molecular structure and pheromone composition as well as sexual compatibility between the two species as found in various research studies. Bactrocera dorsalis is commonly known as the Oriental fruit fly. Bactrocera dorsalis also occurs in several countries in Asia, in Hawaii and in some Pacific islands. In this communication and in the future we will therefore refer to Bactrocera dorsalis (Oriental fruit fly) instead of Bactrocera invadens.

2 Status of Oriental fruit fly in South Africa The current status of the Oriental fruit fly (OFF) in the different regions as from February 2015 (Fig. 1) is as follows: 1. Absent - Regions where OFF is considered absent based on official surveillance are as follows: I. Gert Sibande district municipality in Mpumalanga Province, II. Dr Kenneth Kaunda district municipality and Dr Ruth S. Mompati district municipality in North-West Province III. Amajuba district municipality, umgungundlovu district municipality, umzinyathi district municipality, uthukela district municipality and the Zululand district municipality in KwaZulu-Natal Province, IV. The City of Johannesburg, West Rand, Ekurhuleni and Sedibeng in Gauteng Province, V. Northern Cape Province (pest eradicated in the following district municipalities: John Taolo Gaetsewe, Frances Baard and Z.F. Mgcawu) VI. Free State, Eastern Cape and Western Cape Provinces In regions where OFF is absent, growers should monitor and keep monitoring records. 2. Transient and under eradication - Region where OFF is considered transient, actionable and under eradication is as follows: I. Nkangala district municipality in Mpumalanga Province In regions where eradication actions for OFF are ongoing, growers and land users are served with quarantine orders from DAFF and should adhere to the instructions of the orders which include monitoring and control actions for OFF.

3 3. Present Regions where OFF is considered present are as follows: II. Limpopo Province: a. Vhembe district municipality: Present but subject to official control b. Mopani district municipality: Present but subject to official control c. Sekhukhune district municipality: Present, only in some areas where host crop(s) are grown and subject to official control d. Capricorn district municipality: Present, only in some areas where host crop(s) are grown and subject to official control e. Waterberg district municipality: Present, only in some areas where host crop(s) are grown and subject to official control III. Mpumalanga Province: a. Ehlanzeni district municipality: Present but subject to official control IV. North-West Province: a. Ngaka Modiri Molema district municipality: Present only in some areas but subject to official control b. Bojanala Platinum district municipality: Present at low prevalence, seasonal in some areas and subject to official control V. Gauteng Province a. City of Tshwane: Present seasonally in some areas and subject to official control VI. KwaZulu-Natal Province: a. Ilembe district municipality: Present at low prevalence only in some areas and subject to official control b. Harry Gwala district municipality: Present at low prevalence only in some areas and subject to official control c. Ugu district municipality: Present at low prevalence only in some areas and subject to official control d. umkhanyakude district municipality: Present only in some areas and subject to official control e. uthungulu district municipality: Present at low prevalence only in some areas and subject to official control

4 Figure 1: The current status of B. dorsalis in South Africa as from February In regions where OFF is present, growers should: Manage the pest to prevent crop infestation. Take measures to ensure that fruit that is moved out of the area is not infested with OFF. For Vhembe district municipality in Limpopo province, this will be in accordance with R110 of the Agricultural Pests Act. For other affected regions, growers and land users under quarantine orders from DAFF should adhere to the instructions of the orders which include monitoring and control actions for OFF.

5 High catches of OFF are being recorded in a number of regions where the pest is present in the current period (February). Control actions targeting OFF and other fruit fly pests should be in place in all commercial orchards Now That You Know Your Region s Status, This Is What You Should Do: 1. Status: Absent Monitor with Methyl Eugenol (ME) and dichlorvos in bucket traps (1 trap / 100 ha). Keep accurate trapping records, servicing traps every second week and replacing lure and toxicant every 6-8 weeks. Keep all suspect specimens collected in a vial and clearly label the vial with the PUC / trap number, host plant wherein trap is hung & collection date. Report suspect specimens to the surveillance co-ordinator. Contact details of the co-ordinators are as follows: o Citrus Aruna Manrakhan: aruna@cri.co.za, o Deciduous fruit including grapes Leslie Brown: Leslie@hortgro.co.za, o Subtropical fruit Wilna Stones: Wilna@subtrop.co.za, o Small and new fruit crops - Elrita Venter: elrita@alternafruit.co.za, o All other fruit and vegetable crops DAFF- Jan Hendrik Venter: janhendrikv@daff.gov.za, Apply measures for control of other fruit fly species present.

6 2. Status: Under eradication Adhere to orders issued by DAFF to affected farms. Increase trapping density on farms to 3-5 ME baited traps per 100 ha. Carry out all other actions as detailed in Status: Absent above. Orchard sanitation once a week. Baiting in orchards with either weekly sprays of GF-120 or a mixture of protein hydrolysate and malathion or trichlorfon (pre-harvest intervals for malathion and trichlorfon for different markets should be adhered to) or placement of M3 bait stations. Baiting in orchards should start at least 2 months before earliest harvest dates. If OFF is detected in traps in orchards, apply Male Annihilation Technique (MAT) 1 in addition to the measures above. If fruit is to be moved out of the quarantine area, apply for a removal permit according to instructions on the order issued by DAFF. Contact persons: MashangoaneM@daff.gov.za ( ) and MogaletloaMA@daff.gov.za ( ). Eradication success needs to be verified by DAFF after a period of 8 weeks of no trap catches. DAFF will then verify that all MAT products are removed. Thereafter, monitoring must continue for a further 4 weeks. If, during this 4 week period, there are no further trap catches, DAFF will declare the eradication successful. DAFF will assist, wherever possible, with supply of protein baits and MAT products, in particular for control in residential areas near to production areas. 1 In MAT, OFF males are targeted using ME and killed by an insecticide incorporated with ME. With high levels of male kills, the number of matings and therefore viable offspring are reduced. A number of male annihilation methods such as wooden fibre blocks impregnated with ME and malathion (e.g. Invader-b-Lok, B.i ToolKit), SPLAT technology containing ME and spinosad such as STATIC Spinosad ME and gels containing ME and permethrin (e.g. Last Call B.i) are commercially available for control of OFF in South Africa.

7 3. Status: Present Monitor with ME and dichlorvos in bucket traps (2-4 traps / 100 ha). Keep accurate trapping records, servicing traps every second week and replacing lure and toxicant every 6-8 weeks. Orchard sanitation once a week. Baiting in orchards with either weekly sprays of GF-120 or mixture of protein hydrolysate and malathion or trichlorfon (pre-harvest intervals for malathion and trichlorfon for different markets should be adhered to) or placement of M3 bait stations. Apply MAT together with baiting. To move fruit out of the area where OFF is classified as Present, apply to DAFF for a removal permit. Contact persons: Mercia Rossouw. Tel: / MerciaR@nda.agric.za or DebraM@daff.gov.za OTHER USEFUL INFORMATION Suppliers of trapping materials and MAT products: River Bioscience (Pty) Ltd: / info@riverbioscience.co.za Insect Science (Pty) Ltd: / info@insectscience.co.za Chempac (Pty) Ltd : / info@chemp.co.za Dow AgroSciences Southern Africa (Pty) Ltd : Details to be supplied when reporting possible specimens of OFF trapped in regions where the pest is absent or under eradication/control PUC number. Trap number / orchard name or number.

8 Date trap was serviced. GPS coordinates of the trap (if available). Host plants / commodity surrounding the trap. Bactrocera invadens action plan & Bactrocera invadens trapping guideline South Africa s official plan for the management of OFF and the trapping guideline are available on the following websites: Document drafted on behalf of Bactrocera invadens Steering Committee Contributors: Aruna Manrakhan & Vaughan Hattingh, CRI Derek Donkin, Elsje Kleynhans, Wilna Stones, Subtrop